What are the two main classifications of lasers based on their output?

The primary distinction of lasers based on their output lies in the way they emit light energy, which is classified as either continuous wave (CW) lasers or pulsed lasers. Continuous wave lasers produce a steady stream of light energy without interruption, which allows for consistent and stable applications, often preferred in therapeutic settings where prolonged exposure is needed. This quality makes CW lasers highly beneficial for procedures requiring continuous energy delivery.

On the other hand, pulsed lasers emit energy in short bursts or pulses, which can be advantageous for targeting specific tissues while minimizing heat buildup in surrounding areas. This mode of operation allows for precise applications, particularly in scenarios where thermal damage needs to be controlled, such as in certain aesthetic and medical treatments.

The other classifications mentioned in the options focus on different criteria such as power levels or applications rather than the fundamental nature of the laser output itself, which is why they do not fit the question regarding classifications based on output.